Frequency or channel scanners are generally used in network planning. A scanner used in cellular communication networks, such as the Global System for Mobile Communications (GSM), can determine the signal strength of signals transmitted on channels in the wireless network spectrum, allowing carriers or users of the network to determine the best locations to receive service or where better service is needed or not needed. Scanners may generally scan all frequencies or subset of frequencies of the communication network spectrum and sample information from any frequencies that are identified. Generally speaking, signals are only detected on frequencies used by base stations in the area.
Accordingly, the scanner can sample signals on the identified frequencies and decode information transmitted over the channels to obtain identifying information, such as a base station identification code (BSIC). A base station identification code is a unique identifier used in GSM to identify a base station. When considering the size of the spectrum or network, the number of channels being scanned directly affects the amount of time required to scan the network spectrum and to decode the channel information.
Typically, each cell of the cellular communication network is assigned a unique base station control channel (BCCH). Each cell is also assigned a BSIC. A BCCH is a broadcast channel used by a base station to send information about the identity of the network. Depending on the power output of the base station, the BCCH, BSIC pair will be unique for a cell range radius.